Rocket.Chat is a production-grade, self-hosted team communication platform that provides real-time messaging, voice/video conferencing, omnichannel customer support (livechat), federation (Matrix), and an extensible app marketplace. The system is architected as a monorepo with a Meteor-based main application (apps/meteor) serving both the client (React with Fuselage UI) and server (Meteor methods, REST APIs via Hono, and microservices for enterprise features). Enterprise services (e.g., account, presence, authorization, DDP streamer) are implemented as separate polka-based microservices and gated by a license module. The client leverages React, TanStack Query, Zustand, and a rich component library (packages/ui-client). Data flows primarily through MongoDB (via typed model layers) with real-time updates pushed over DDP/WebSockets. File uploads use S3 or GridFS. Federation is achieved via Matrix protocol integration. The apps engine (packages/apps-engine) allows third-party apps to hook into message, room, and user events through a bridge pattern. The codebase includes extensive unit tests (Jest, Mocha), integration tests, Playwright e2e tests, and Storybook with a11y checks. External dependencies include MongoDB, Meteor, React, i18next, and a large set of npm packages managed by Yarn workspaces. The repository is actively maintained with frequent commits, changesets for versioning, and CI/CD pipelines.
ClickClack is a production-grade, self-hostable team chat platform built for people, bots, and agents. The backend is a single Go binary serving a REST API with WebSocket real-time events, supporting both SQLite and PostgreSQL as interchangeable storage backends. The frontend is a Svelte 5 single-page application embedded into the Go binary, with an optional Electron desktop client and a TypeScript SDK for bot development. The system provides workspaces, channels, threads, direct messages, file uploads, full-text search, reactions, pinned messages, slash commands, event subscriptions, and push notifications (Web Push and Pushover). Authentication supports magic links, passwords (Argon2id), GitHub OAuth, and Cloudflare Access JWT. The architecture emphasizes security with SSRF-safe callback dialers, strict cookie namespacing, rate limiting, and bot scope enforcement. The codebase is notable for its dual-database store pattern with shared contract tests, a real-time event hub with cursor-based recovery, and a comprehensive test suite including unit, integration, and Playwright end-to-end tests. It is not a data research project; it is a fully featured application designed for self-hosting or cloud deployment.
Zulip is a production-grade, open-source team chat application built as a Django monolith with a real-time Tornado event server. The backend uses Django ORM with PostgreSQL, RabbitMQ for async queue processing (email, push notifications, URL previews), Memcached/Redis for caching and rate limiting, and a custom typed-endpoint decorator pattern for API validation. The frontend is a mix of legacy jQuery/Handlebars and modern TypeScript with Zod schemas, Webpack bundling, and extensive UI components for chat composition, streams, topics, user groups, and settings. The system exposes a REST API (used by mobile and desktop clients), webhook ingestion for 50+ third-party services, and a full billing/support subsystem via Stripe. The architecture is a single monolithic Django application with separate Tornado process for real-time push, alongside queue workers and cron-like management commands. Key entry points include the Django WSGI server, Tornado event server, management commands (e.g., manage.py), and webhook view functions. External dependencies include PostgreSQL, RabbitMQ, Redis, Memcached, Stripe, pgroonga (full-text search), pyvips (image processing), and numerous npm packages.